Breaking News
News & Analysis

Lowest Power MEMS Mic Cuts Noise

7/6/2014 00:00 AM EDT
6 comments
NO RATINGS
More Related Links
View Comments: Oldest First | Newest First | Threaded View
goafrit
User Rank
Author
MEMS Noise
goafrit   7/6/2014 3:57:20 PM
NO RATINGS
>> Knowles claims its world's lowest-power MEMS mic with a signal-to-noise (SNR) of 64.3 dB measures just 3.50 x 2.65 x 0.98 millimeters. (Source: Knowles)

It is fair to say that Knowles could be right. They are the industry leading mic MEMS maker. Though ST takes the bulk of the business because of its scale and business with Apple, Knowles does a lot of great works in this space.

DrFPGA
User Rank
Author
Serial PDM
DrFPGA   7/6/2014 5:37:33 PM
NO RATINGS
Too bad its not a moe standard interface. Perhaps this would increase power requirements? If so, maybe we need a new very low power seial interface standard....

R_Colin_Johnson
User Rank
Author
Re: MEMS Noise
R_Colin_Johnson   7/6/2014 9:33:58 PM
NO RATINGS
Knowles has a 59 percent share of the global market according to IHS and has two mics in the iPhone5s according to Yoles.

R_Colin_Johnson
User Rank
Author
Re: Serial PDM
R_Colin_Johnson   7/9/2014 7:26:22 PM
NO RATINGS
I finally got an answer as to why they use PDM. Here's what they say:

"We selected the PDM interface based on our experience working with major OEMs around the world and the industry's adoption of PDM as the standard microphone interface. Within the analog-to-digital conversion, the PDM interface allows the microphone to contain the entire analog process with a digital output to the Codec or application processor. A digital output from the microphone enables the Codec and application processor to be more efficient in terms of size, scale, and power consumption. This also helps eliminates the need for a high power analog-to-digital converter between the microphone and the Codec or application processor."

goafrit
User Rank
Author
Re: MEMS Noise
goafrit   7/9/2014 8:34:04 PM
NO RATINGS
>> Knowles has a 59 percent share of the global market according to IHS and has two mics in the iPhone5s according to Yoles.

Makes sense because I knew when we struggled in the industry to get pass the IPs Knowles has in MEMS micr. They have eaten the launch in this sector and will continue to stay on top unless they blow it. It is like in XL, there is one patent ST has in charge pump that enables you to ramp up  voltage that makes everyone struggle.

DrFPGA
User Rank
Author
Re: Serial PDM
DrFPGA   7/9/2014 10:56:51 PM
NO RATINGS
Thanx for the follow-up. Looks like they target the high volume (application processor) market so PDM makes sense...

Most Recent Comments
michigan0
 
SteveHarris0
 
realjjj
 
SteveHarris0
 
SteveHarris0
 
VicVat
 
Les_Slater
 
SSDWEM
 
witeken
Most Recent Messages
9/25/2016
4:48:30 PM
michigan0 Sang Kim First, 28nm bulk is in volume manufacturing for several years by the major semiconductor companies but not 28nm FDSOI today yet. Why not? Simply because unlike 28nm bulk the LDD(Lightly Doped Drain) to minimize hot carrier generation can't be implemented in 28nm FDSOI. Furthermore, hot carrier reliability becomes worse with scaling, That is the major reason why 28nm FDSOI is not manufacturable today and will not be. Second, how can you suppress the leakage currents from such ultra short 7nm due to the short channel effects? How thin SOI thickness is required to prevent punch-through of un-dopped 7nm FDSOI? Possibly less than 4nm. Depositing such an ultra thin film less then 4nm filum uniformly and reliably over 12" wafers at the manufacturing line is extremely difficult or not even manufacturable. If not manufacturable, the 7nm FDSOI debate is over!Third, what happens when hot carriers are generated near the drain at normal operation of 7nm FDSOI? Electrons go to the positively biased drain with no harm but where the holes to go? The holes can't go to the substrate because of the thin BOX layer. Some holes may become trapped at the BOX layer causing Vt shift. However, the vast majority of holes drift through the the un-dopped SOI channel toward the N+Source,...

Datasheets.com Parts Search

185 million searchable parts
(please enter a part number or hit search to begin)
Like Us on Facebook
EE Times on Twitter
EE Times Twitter Feed